Radar-Derived Structural and Precipitation Characteristics of ZDR Columns within Warm-Season Convection over the United Kingdom

AbstractAnalyses of the radar-observed structure and derived rainfall statistics of warm-season convection developing columns of enhanced positive differential reflectivity ZDR over England’s southwest peninsulaare presented here. Previous observations of ZDR columns in developing cumulonimbus clouds over England were rare. The observations presented herein suggest otherwise, at least in the southwesterly winds over the peninsula. The results are the most extensive of their kind in the United Kingdom; the data were collected using the National Centre for Atmospheric Sciencedual-polarization X-band radar (NXPol) during the Convective Precipitation Experiment (COPE). In contrast to recent studies of ZDR columns focused on deep clouds that developed in high-instability environments, the COPE measurements show relatively frequent ZDR columns in shallower clouds, many only 4–5 km deep. The presence of ZDR columns is used to infer that an active warm rain process has contributed to precipitation evolution in ...